Question

After reading 2/3 of a book, 20 pages are left. How many pages are there in the book?​

Answer 1

$\large{ \dag \: { \rm{ \underline{Solution}}}}$

Let the total no. of pages to be x.

According to the question,

$\: \: \: \: \implies \frac{2x}{3} = x - 20$

$\: \: \: \: \implies{ \frac{2x}{3} = x - 20 }$

$\: \: \: \: \implies{ \frac{2x}{3} - \frac{x}{1} = ( - 20)}$

$\: \: \: \: \implies{ \frac{2x - 3x}{3} = ( - 20)}$

$\: \: \: \: \implies \frac{ - 1x}{3} = (- 20)$

$\: \: \: \: \implies{x = {(\cancel{-} 20}) \times \frac{3}{ \cancel{-} 1} }$

$\: \: \: \: \implies{x = 20 \times 3}$

$\: \: \: \: \implies{ \bold{x = 60}}$

• Hence, there are 60 pages in the book